What is a genre convention?
A genre convention is a typical or standard trope of plot, character, setting, icon, theme, or effect in a genre story. For instance, in a Western it is conventional to have the heroes wear white hats and the villains wear black hats (icon convention) Or in the superhero genre, it is a convention to have the characters wear costumes (icon convention). The easiest way to spot a genre convention is to think about the trope being placed in another genre. For instance in a Western, a church is a sign of civilization and the East; but in a romantic comedy, a church is a sign of reconciliation (through marriage) of the main characters, who usually get married.